Motown: Define MediaRenderer and make it the way we identify renderers.

services/media/factory_service/factory_service.h

Index: services/media/factory_service/factory_service.h
diff --git a/services/media/factory_service/factory_service.h b/services/media/factory_service/factory_service.h
index 0955092f4240903e77b24ce04732aa8e0ecbfdaf..247bf8a0f378e30e739c3a73559b59100582298b 100644
--- a/services/media/factory_service/factory_service.h
+++ b/services/media/factory_service/factory_service.h
@@ -24,13 +24,15 @@ class MediaFactoryService : public util::FactoryServiceBase,
 
   // MediaFactory implementation.
   void CreatePlayer(InterfaceHandle<SeekingReader> reader,
+                    InterfaceHandle<MediaRenderer> audio_renderer,
+                    InterfaceHandle<MediaRenderer> video_renderer,
                     InterfaceRequest<MediaPlayer> player) override;
 
   void CreateSource(InterfaceHandle<SeekingReader> reader,
                     Array<MediaTypeSetPtr> allowed_media_types,
                     InterfaceRequest<MediaSource> source) override;
 
-  void CreateSink(const String& destination_url,
+  void CreateSink(InterfaceHandle<MediaRenderer> renderer,
                   MediaTypePtr media_type,
                   InterfaceRequest<MediaSink> sink) override;